diff --git a/src/main/java/com/github/hcsp/polymorphism/User.java b/src/main/java/com/github/hcsp/polymorphism/User.java
index 51c95dc..cb4b82c 100644
--- a/src/main/java/com/github/hcsp/polymorphism/User.java
+++ b/src/main/java/com/github/hcsp/polymorphism/User.java
@@ -1,14 +1,19 @@
 package com.github.hcsp.polymorphism;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.function.Predicate;
 
 public class User {
-    /** 用户ID，数据库主键，全局唯一 */
+    /**
+     * 用户ID，数据库主键，全局唯一
+     */
     private final Integer id;
 
-    /** 用户名 */
+    /**
+     * 用户名
+     */
     private final String name;
 
     public User(Integer id, String name) {
@@ -24,40 +29,62 @@ public String getName() {
         return name;
     }
 
-    // 过滤ID为偶数的用户
-    public static List<User> filterUsersWithEvenId(List<User> users) {
-        List<User> results = new ArrayList<>();
+    //判断条件是否成立的接口
+    public interface ConditionInterface {
+        boolean conditionWay(User user);
+
+    }
+
+    //根据传入的不同过滤方法来过滤数组
+    public static List<User> filter(List<User> users, Predicate<User> ci) {
+        List<User> result = new ArrayList<>();
         for (User user : users) {
-            if (user.id % 2 == 0) {
-                results.add(user);
+            if (ci.test(user)) {
+                result.add(user);
             }
         }
+        return result;
+    }
+
+    // 过滤ID为偶数的用户
+    public static List<User> filterUsersWithEvenId(List<User> users) {
+        List<User> results = filter(users, new Predicate<User>() {
+            @Override
+            public boolean test(User user) {
+                return user.id % 2 == 0;
+            }
+        });
         return results;
     }
 
+    public static void main(String[] args) {
+        List<User> results = filterZhangUsers (Arrays.asList(new User(1, "a"), new User(2, "a"), new User(3, "a")));
+        System.out.println(Arrays.toString(results.toArray()));
+    }
+
     // 过滤姓张的用户
     public static List<User> filterZhangUsers(List<User> users) {
-        List<User> results = new ArrayList<>();
-        for (User user : users) {
-            if (user.name.startsWith("张")) {
-                results.add(user);
+        List<User> results = filter(users, new Predicate<User>() {
+            @Override
+            public boolean test(User user) {
+                return user.name.startsWith("张");
             }
-        }
+        });
         return results;
     }
 
     // 过滤姓王的用户
     public static List<User> filterWangUsers(List<User> users) {
-        List<User> results = new ArrayList<>();
-        for (User user : users) {
-            if (user.name.startsWith("王")) {
-                results.add(user);
+        List<User> results = filter(users, new Predicate<User>() {
+            @Override
+            public boolean test(User user) {
+                return user.name.startsWith("王");
             }
-        }
+        });
         return results;
     }
     // 你可以发现，在上面三个函数中包含大量的重复代码。
     // 请尝试通过Predicate接口将上述代码抽取成一个公用的过滤器函数
     // 并简化上面三个函数
-    public static List<User> filter(List<User> users, Predicate<User> predicate) {}
+//    public static List<User> filter(List<User> users, Predicate<User> predicate) {}
 }